Small animal litter tray

ABSTRACT

A small animal litter box which comprises an upper tray with a perforated bottom wall for carrying litter material, and a lower tray for receiving urine and particles dropping from the first tray through the perforated bottom wall thereof. The first tray contains litter material in the form of pellets that are disintegrated into smaller particles when the pellets absorb urine, and the perforated bottom wall has holes dimensioned such that smaller particles from disintegrated pellets pass through the holes while intact pellets are prevented from passing through the holes.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Phase application claiming the benefit ofPCT/SE01/00748 filed Apr. 5, 2001 which further claims priority benefitform Swedish application 0001351-6 filed Apr. 12, 2000.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a small animal litter box comprising afirst tray with a perforated bottom wall for carrying litter material,and a second tray situated under the first tray for receiving freelydropping urine and particles that have passed through the perforatedbottom wall of the first tray.

2. Description of the Related Art

A small animal litter box composed of two tray is disclosed in DE 41 27635 A1. In the known litter box the two trays have identicalcircumferential walls with a truncated conical shape. This enablesplacing the first tray telescopically in the second tray, which isintended to stand with its bottom directly on the floor and thus carrythe first tray. The perforated bottom wall has relatively small holeswith a diameter of a few millimeters to permit drainage of urine fromthe first tray to the second tray, whereas all solid substances presentin the first tray are to be prevented from passing the holes.

A problem of the known litter box according to DE 41 27 835 is that itsstands relatively unstable on the floor due to the conical shape of thetrays. This results in the risk of the small animal, for example a cat,or a human tipping over the litter box so that its contents is spreadoutside the litter box.

U.S. Pat. No. 4,848,274 discloses a small animal litter box thatlikewise is composed of an upper tray with a perforated bottom wall anda lower tray for receiving urine. In this case the upper tray isprovided with a sideboard extending downwardly from the upper confiningedge of the tray past the perforated bottom wall. As a result a spacefor the lower tray is defined between the sideboard, the perforatedbottom wall and the floor, when the upper tray is placed on a floor. Bymeans of the sideboard this known small animal litter box stands stableon the floor. Between the perforated bottom wall and the lower traythere is placed a liquid absorbing material. A locking device engagesthe two trays so that the liquid absorbing material is pressed againstthe perforated bottom wall. Thus, solid material can not pass throughthe perforated bottom wall down into the lower tray.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an environmentallyfriendly hygienic small animal litter box, which is easy to keep cleanand which is intended for such kind of animals that have an instinct toburrow there faeces.

This object is obtained by a small animal litter box of the kindinitially stated characterized in that the first tray is intended tocontain litter material in the form of pellets that are disintegratedinto smaller particles when the pellets absorb urine, and the perforatedbottom wall has holes, each of which is dimensioned such that smallerparticles from a disintegrated pellet are able to pass through the holewhile an intact pellet is prevented from passing through the hole.

Hereby the significant advantage is achieved that also litter particlesthat have absorbed urine easily can be removed from the small animallitter box with the aid of the second tray, which is a strikingimprovement in a hygienic sense as compared with traditional smallanimal litter boxes. The risk of polluted litter material getting stuckon the paws of the animal and being transferred to humans issubstantially reduced.

For environmental reasons pellets of compressed wood-shavings with athickness of between 4 and 7 mm can be used. Polluted wood-shavings fromsuch wood-shaving pellets can conveniently be flushed down the toilet.For heating purposes there are currently cylindrical pellets ofcompressed wood-shavings on the market excellent for use in the smallanimal litter box according to the invention. Since these cylindricalpellets have a diameter of about 6 mm the holes of the bottom wall aresuitably designed with a size of about 5 mm in diameter for circularholes. Generally, each hole should not be larger than 90% of the size ofeach pellet.

Advantageously, the sideboard is joined to the first tray and extendsdownwardly from the upper confining edge thereof past the perforatedbottom wall, so that when the first tray is placed on a floor there is aspace defined between the sideboard, the perforated bottom wall and thefloor, wherein the second tray can be placed loose in said space.Besides the advantageous function to keep the first tray stable on thefloor the sideboard also has the function to keep the second tray inplace under the first tray. With the second tray placed loose in saidspace particles from this integrated pellets are thus able to passthrough the perforated bottom wall and drop down into the second tray.

The small animal litter box will be particularly stable if the sideboardis designed as a truncated cone with the base situated on the floor.

The first tray preferably has a corner-less circumferential wall,suitably with oval cross-section, which makes the tray easy to clean. Tofurther facilitate cleaning of the first tray the corner-lesscircumferential wall suitably has the shape of a truncated cone with thebase situated at the upper confining edge of the circumferential wall.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical cross-section through a small animal litter boxaccording to the invention placed on a floor;

FIG. 2 is a view obliquely from above of an upper tray of the smallanimal litter box according to FIG. 1; and

FIG. 3 is a view obliquely from above of a lower tray of the smallanimal litter box according to FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to the figures there is shown a small animal litter box 1comprising an upper tray 2 having a conically inwardly taperingcircumferential wall 3 with an oval cross-section, and a perforatedbottom wall 4 with circular holes 5. The holes 5 have a diameter ofabout 5 mm and are distributed across the entire bottom wall 4 with adistance between the centers of adjacent holes 5 of 15 mm. From theupper circumferential edge 6 of the circumferential wall 3 the sideboard7 extends conically outwardly and downwardly past the bottom wall 4 to afloor 8, so that a space is defined between the sideboard 7, the bottomwall 4 and the floor 8. The tray 2 and the sideboard 7 are made in onesingle piece.

A lower tray 10 is placed loose in the space 9 under the perforatedbottom wall 4. The tray 10 has an oval shape adapted to the upper tray2, so that the tray 10 extends under the entire perforated bottom wall4.

Both the tray 2 including the sideboard 7 arranged thereto and the tray10 are suitably made of a rigid plastic material.

The small animal litter box illustrated is dimensioned in view of theanimal species it is to serve, for example cat, rabbit, guinea-pig, rator the like. With respect to the dimensioning of the box, considerationis also taken with regard to the eagerness of the animal species toscratch the litter material.

When using the small animal litter box according to the invention arelatively thin layer, about 1 to 2 cm thick, of wood-shaving pellets isplaced on the bottom wall 4 of the upper tray 2. When, for example, acat sits in the tray 2 to urinate, most of the urine will directly passthe thin layer of pellets through the holes 5 down into the lower tray10. After the cat has relieved itself it will scratch over the pelletssteeped in urine which causes other, now dry, pellets that havepreviously absorbed urine to disintegrate into smaller particles. Thesmaller particles that arise when the pellets are disintegrated drop, bythe effect of the scratching of the cat, down through the holes 5 andare collected in the lower tray 10. When the cat defecates,wood-shavings will deposit on the surface of the feces, so that thefeces easily can be removed from the upper tray 2 and advantageously beflushed away in a water closet.

Normally, each hole 5 has a diameter of between 4 and 7 mm, preferably 5mm. Litter material for use in the small animal litter box consists ofwood-shavings compressed to pellets with a thickness of between 4 and 7mm, preferably 6 mm.

1. A combination small animal litter box and litter material comprising;a litter box including a first tray having a perforated bottom wallincluding a plurality of holes, a litter material consisting of intactpellets of a first size which is larger than a dimension of each of theplurality of holes in said first tray, the pellets being formed of amaterial that disintegrates into smaller particles after absorbing urineand wherein the smaller particles are of a size to pass through theholes in said bottom wall of said first tray, said intact pellets beingprovided in said first tray, a second tray situated under said firsttray for receiving freely falling urine and the smaller particles thathave been formed by the disintegration of the intact pellets byabsorbing urine and subsequently passed through the perforated bottomwall of said first tray, whereby substantially only urine absorbedsmaller particles pass through the holes in the perforated bottom wallof said first tray and into said second tray while remaining intactpellets, which have not absorbed urine to enable them to disintegrate,are too large and are thus prevented from passing through the holes insaid first tray.
 2. The small animal litter box of claim 1 wherein eachhole in the perforated bottom wall is circular with a diameter that isat most 90% of a diameter of the intact pellets.
 3. The small animallitter box according to claim 1, wherein the intact pellets are formedof compressed wood-shavings.
 4. The small animal litter box of claim 3wherein the intact pellets have a thickness of between 4 and 7 mm. 5.The small animal litter box of claim 4 wherein the intact pellets have athickness of approximately 6 mm.
 6. The small animal litter box of claim1 wherein each hole has a diameter of between 4 and 7 mm.
 7. The smallanimal litter box of claim 6 wherein each hole has a diameter ofapproximately 5 mm.